The month of December is uniquely represented in the world of gemstones not by a single stone, but by a captivating duo: the historic, earthy Turquoise and the modern, vibrant Tanzanite. These two gems, each with its own distinct character and allure, offer those born in the final month of the year a choice between timeless tradition and contemporary elegance. While Turquoise has been cherished for millennia for its protective qualities and distinctive blue-green hue, Tanzanite is a relative newcomer, celebrated for its mesmerizing violet-blue shades and rapid rise to prominence in the gemological world. Together, they form a rich tapestry of color, meaning, and history, making December's birthstone jewelry a truly special category for collectors and gift-givers alike. This article will explore the geological origins, gemological properties, historical lore, and modern symbolism of these two remarkable stones, providing a complete guide for enthusiasts and prospective owners.
Historical Significance and Lore
The story of December's birthstones is a tale of ancient heritage meeting modern discovery. Turquoise stands as one of the oldest known gemstones in human history, its use dating back thousands of years.
Turquoise: The Ancient Talisman For centuries, Turquoise has been revered across numerous cultures, particularly in Ancient Egypt, where it was used extensively in jewelry and ceremonial objects. Its name is derived from the French "pierre turquoise," meaning "Turkish stone," reflecting the historical trade routes through which it reached Europe. The stone was not merely an ornament; it was a powerful amulet. Civilizations such as the Persians and Native American tribes believed Turquoise possessed protective powers, capable of warding off evil and ensuring safety during travel. It was often set into shields, swords, and bridles, as well as worn as jewelry. The stone's association with the sky and water led to beliefs in its ability to provide calm, tranquility, and good fortune. Its status as a traditional birthstone is deeply rooted in this long and storied history of human use and belief.
Tanzanite: The Gem of a Generation In stark contrast to Turquoise's ancient lineage, Tanzanite is a 20th-century discovery. It was first found in the Merelani foothills of Mount Kilimanjaro in Tanzania in 1967. Initially, the blue-violet mineral zoisite was mistaken for sapphire due to its rich color. Upon analysis, it was identified as a new variety and was later named "Tanzanite" in honor of its single source country. The Tiffany & Co. jewelry company recognized its potential and launched a major marketing campaign in 1968, propelling it onto the global stage. Due to its limited geographic origin and stunning beauty, it was quickly embraced as a modern alternative birthstone for December, offering a fresh and luxurious option for those seeking a gem with a contemporary story.
Geological Formation and Sources
The origins of these two gemstones could not be more different, reflecting their contrasting histories and appearances.
Turquoise: A Hydrated Mineral Turquoise is not a silicate mineral like most traditional gemstones but is a hydrated phosphate of copper and aluminum. It forms in arid regions where acidic, copper-rich groundwater percolates through aluminum-bearing rocks. Over geological time, this process deposits minerals in cracks and voids, creating the nodular or vein-like formations of Turquoise. Its characteristic blue-green color is directly derived from the presence of copper (blue) and iron (green). Major sources for Turquoise include the United States (particularly Arizona and Nevada, known for "Spiderweb" matrix Turquoise), Iran (historically the source of the finest "robin's egg blue" material), and China. The quality and appearance of Turquoise vary significantly based on its source, with some being a solid, uniform color and others featuring a distinctive "matrix" of the host rock within the gem.
Tanzanite: A Single Source Phenomenon Tanzanite's geological story is one of extreme rarity. It is found in only one location on Earth: a small, four-square-kilometer mining area in the Merelani Hills of northern Tanzania. It formed millions of years ago when intense heat and pressure altered the parent rock (geode), creating the unique conditions for the blue-violet zoisite to grow. This event was a geological anomaly, explaining why the gem is not found anywhere else in the world. This single-source origin makes Tanzanite inherently rare, and its supply is finite, adding to its value and allure. The mining area is divided into blocks, with different blocks known for producing different qualities of the gem.
Gemological Properties
Understanding the physical and chemical characteristics of these stones is crucial for appreciating their unique qualities and for their proper care.
| Property | Turquoise | Tanzanite |
|---|---|---|
| Chemical Composition | Hydrated phosphate of copper and aluminum (CuAl₆(PO₄)₄(OH)₈·4H₂O) | Calcium aluminum silicate hydroxide (Ca₂Al₃(SiO₄)₃(OH)) |
| Color | Sky blue to blue-green; often features a brown or black matrix | Typically a vibrant, saturated violet-blue; can be a lighter lavender-blue in smaller sizes |
| Hardness (Mohs Scale) | 5 to 6 | 6.5 to 7 |
| Crystal System | Triclinic | Orthorhombic |
| Transparency | Opaque to semi-translucent | Transparent to translucent |
| Luster | Waxy to subvitreous | Vitreous (glass-like) |
As the table indicates, Tanzanite is a harder and more durable gemstone than Turquoise, making it more suitable for pieces that might experience daily wear, such as rings. Turquoise, being softer and often porous, requires more careful handling. The color of Tanzanite is its most defining feature. It is strongly trichroic, meaning it can show three different colors—blue, violet, and a reddish-brown—depending on the crystal orientation. Most gems are cut to display the dominant blue-violet hue, which is often enhanced through a controlled heating process to remove the brownish tints and stabilize the color. Turquoise's color is natural, though it can be stabilized with wax or resin to improve its durability and luster.
Symbolism and Metaphysical Beliefs
Both stones are rich in symbolism, which contributes to their popularity in birthstone jewelry.
- Turquoise is widely regarded as a stone of protection, serenity, and good fortune. It is believed to promote inner calm, balance, and honest communication. In many traditions, it is considered a "master healer" that can absorb negative energy and purify the user's aura. Its connection to the sky and water symbolizes wisdom, tranquility, and a deep connection to nature.
- Tanzanite, as a newer gem, has developed its own set of metaphysical associations, often linked to its modern origins and unique energy. It is known as a stone of transformation, spiritual awakening, and intuition. Believers suggest it can open the mind to new perspectives, stimulate the "Third Eye" chakra for enhanced perception, and encourage a higher level of consciousness. It is also associated with creativity and the expression of one's unique truth.
Care and Cleaning
Proper maintenance is essential to preserve the beauty and integrity of any gemstone. Due to their differing hardness and stability, Turquoise and Tanzanite require distinct care regimens.
Caring for Turquoise With a Mohs hardness of only 5 to 6, Turquoise is relatively soft and susceptible to scratching. It is also porous and can be damaged by chemicals. To clean it, use only warm water, a mild soap, and a soft cloth. Avoid ultrasonic cleaners, steam cleaners, and harsh chemicals like household detergents, perfumes, and lotions, as these can strip the stone of its polish or cause discoloration. It is advisable to store Turquoise jewelry separately to prevent it from being scratched by harder stones.
Caring for Tanzanite Tanzanite is more durable, with a hardness of 6.5 to 7, but it possesses perfect cleavage in one direction, meaning it can be easily fractured if struck with force. This makes it vulnerable to damage from sharp blows. It is also sensitive to rapid temperature changes. The best cleaning method for Tanzanite is warm water, a mild detergent, and a soft brush. As with Turquoise, ultrasonic and steam cleaners are not recommended. It is best to remove Tanzanite jewelry before engaging in activities where it could be knocked or exposed to hard impacts.
Conclusion
The December birthstones, Turquoise and Tanzanite, offer a compelling duality that caters to a wide range of tastes and styles. Turquoise represents a connection to ancient history, nature, and the enduring belief in protection and tranquility. Its earthy, opaque beauty speaks of tradition and grounded elegance. Tanzanite, on the other hand, is a testament to modern gemology—a rare, brilliant gem born from a unique geological event, symbolizing transformation and visionary insight. The choice between them is not about which is superior, but which resonates more deeply with the wearer. Whether one is drawn to the timeless, protective charm of Turquoise or the vibrant, transformative energy of Tanzanite, both gems provide a meaningful and beautiful way to celebrate a December birthday.